I've only played for two hours last night (Squad, that is) but it was incredibly fun, some of the changes are brilliant. Ammo being persistent up to a certain point adds utility to the basic role of rifleman which can now resupply the squad and also reinforces the importance of well placed and supplied FOBs. I bet we will see many vehicle hunting fireteams composed of one LAT/HAT, one rifleman and one medic.
Speaking of fireteams, they're great when SLs make proper use of them. I was playing on the RIP server last night and two clan members were successfully dealing with the challenge of leading our squad to victory, splitting us into two teams that were pushing from two angles or defending different areas of flag zones.
I also like the changes for healing, now any role can revive others using bandages but unless you get revived by a medic, you're left with low health and zero stamina until one heals you with the medic bag. This relieves some of the stress on medics but also makes them even more essential than before since you're pretty much useless with low stamina (weapon sway, etc). It also fits thematically, I should be able to patch someone up quickly with a bandage despite not having advanced medical training.
As for tanks.. that's just the icing on the cake, I've never experienced anything as deafening and imposing in a shooter as last night when I was caught in the middle of a fight between two Abrams, one T-72 and two BTRs. The sounds, man, the sounds and the horror of being a pesky rifleman..
Looking forward to playing more!